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U.S. astronauts are climbing back into space capsules. Here's howthey've improved over the past 50 years
"In 1961, an American astronaut reached space for the first time and soared
through the heavens in a gumdrop-shaped capsule. Since then, people have flown to the moon, created space planes and designed rockets that return to Earth for precision landings. But when astronauts lift off next year from U.S. soil for the first time in six years, their vehicle of choice will be another capsule." See: http://www.latimes.com/business/la-f...htmlstory.html How do the benefits of capsules and spaceplanes compare? |
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U.S. astronauts are climbing back into space capsules. Here's howthey've improved over the past 50 years
On Friday, September 15, 2017 at 11:44:09 AM UTC-7, Fred J. McCall wrote:
wrote: "In 1961, an American astronaut reached space for the first time and soared through the heavens in a gumdrop-shaped capsule. Since then, people have flown to the moon, created space planes and designed rockets that return to Earth for precision landings. But when astronauts lift off next year from U.S. soil for the first time in six years, their vehicle of choice will be another capsule." See: http://www.latimes.com/business/la-f...htmlstory.html How do the benefits of capsules and spaceplanes compare? Capsules have lower dry mass for the cargo they carry, since you're not carrying along all that lifting structure. I was rather disappointed to see SpaceX back away from a powered landing on land for the Dragon V2, since that would have addressed one of the advantages of spaceplanes in that they don't require 'recovery forces' to fish them out of the water. Small spaceplanes tend to be more 'reusable' than capsules. However, the fiasco that was the Space Shuttle backed everyone away from the idea of spaceplanes. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw The USAF still likes spaceplanes: https://www.space.com/25275-x37b-space-plane.html https://www.space.com/36985-darpa-xs...m-express.html There's also Dreamchaser: https://www.space.com/37636-dream-ch...v-rockets.html The Chinese and Europeans also have spaceplane projects: https://www.theverge.com/2016/10/5/1...rism-20-people http://www.bbc.com/future/story/2017...nside-a-rocket But SpaceX, NASA, and the Russians are still sticking with capsules. |
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U.S. astronauts are climbing back into space capsules. Here's how they've improved over the past 50 years
wrote:
On Friday, September 15, 2017 at 11:44:09 AM UTC-7, Fred J. McCall wrote: wrote: "In 1961, an American astronaut reached space for the first time and soared through the heavens in a gumdrop-shaped capsule. Since then, people have flown to the moon, created space planes and designed rockets that return to Earth for precision landings. But when astronauts lift off next year from U.S. soil for the first time in six years, their vehicle of choice will be another capsule." See: http://www.latimes.com/business/la-f...htmlstory.html How do the benefits of capsules and spaceplanes compare? Capsules have lower dry mass for the cargo they carry, since you're not carrying along all that lifting structure. I was rather disappointed to see SpaceX back away from a powered landing on land for the Dragon V2, since that would have addressed one of the advantages of spaceplanes in that they don't require 'recovery forces' to fish them out of the water. Small spaceplanes tend to be more 'reusable' than capsules. However, the fiasco that was the Space Shuttle backed everyone away from the idea of spaceplanes. The USAF still likes spaceplanes: https://www.space.com/25275-x37b-space-plane.html https://www.space.com/36985-darpa-xs...m-express.html The USAF thinks they're made of money and note that it doesn't do anything that either a capsule OR a regular spaceplane would do. There's also Dreamchaser: https://www.space.com/37636-dream-ch...v-rockets.html Assuming they finish it. Note that Dragon carries 20% more cargo (by weight) and is available now vice Dream Chaser perhaps being available in 2021. That difference in payload as well as the Dream Chaser decision to launch on ULA launchers is going to make it significantly more expensive per launch. The Chinese and Europeans also have spaceplane projects: https://www.theverge.com/2016/10/5/1...rism-20-people Not an orbital system and still largely dreamware. http://www.bbc.com/future/story/2017...nside-a-rocket Like the USAF system. Too small to do much (assuming they finish it). But SpaceX, NASA, and the Russians are still sticking with capsules. Because they're all in the business of actually putting stuff in orbit. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw |
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U.S. astronauts are climbing back into space capsules. Here's how they've improved over the past 50 years
"Fred J. McCall" wrote in message
... wrote: "In 1961, an American astronaut reached space for the first time and soared through the heavens in a gumdrop-shaped capsule. Since then, people have flown to the moon, created space planes and designed rockets that return to Earth for precision landings. But when astronauts lift off next year from U.S. soil for the first time in six years, their vehicle of choice will be another capsule." See: http://www.latimes.com/business/la-f...htmlstory.html How do the benefits of capsules and spaceplanes compare? Capsules have lower dry mass for the cargo they carry, since you're not carrying along all that lifting structure. I was rather disappointed to see SpaceX back away from a powered landing on land for the Dragon V2, since that would have addressed one of the advantages of spaceplanes in that they don't require 'recovery forces' to fish them out of the water. Small spaceplanes tend to be more 'reusable' than capsules. However, the fiasco that was the Space Shuttle backed everyone away from the idea of spaceplanes. My understanding is that NASA is the one insisting on a water landing for Dragon V2, but SpaceX for its own missions still plans to ultimately do land landings. I expect we'll eventually see us move back towards small spaceplans/lifting body designs in a few decades, but it'll take some time. -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net IT Disaster Response - https://www.amazon.com/Disaster-Resp...dp/1484221834/ |
#6
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U.S. astronauts are climbing back into space capsules. Here's how they've improved over the past 50 years
In article ,
says... "Fred J. McCall" wrote in message ... wrote: "In 1961, an American astronaut reached space for the first time and soared through the heavens in a gumdrop-shaped capsule. Since then, people have flown to the moon, created space planes and designed rockets that return to Earth for precision landings. But when astronauts lift off next year from U.S. soil for the first time in six years, their vehicle of choice will be another capsule." See: http://www.latimes.com/business/la-f...htmlstory.html How do the benefits of capsules and spaceplanes compare? Capsules have lower dry mass for the cargo they carry, since you're not carrying along all that lifting structure. I was rather disappointed to see SpaceX back away from a powered landing on land for the Dragon V2, since that would have addressed one of the advantages of spaceplanes in that they don't require 'recovery forces' to fish them out of the water. Small spaceplanes tend to be more 'reusable' than capsules. However, the fiasco that was the Space Shuttle backed everyone away from the idea of spaceplanes. My understanding is that NASA is the one insisting on a water landing for Dragon V2, but SpaceX for its own missions still plans to ultimately do land landings. This has changed somewhat recently. Reportedly SpaceX is the one who shelved development of Dragon V2 vertical landing. The reasons for this aren't terribly clear, but there are hints from SpaceX that this is because they've decided to change the (Mars) landing mode of their (eventual) Mars vehicle. Also, SpaceX is supposed to have a press briefing about the changes in their Mars program sometime this fall. Hopefully we'll get more information then which will allow us to "connect the dots". I expect we'll eventually see us move back towards small spaceplans/lifting body designs in a few decades, but it'll take some time. Possibly. Sierra Nevada Corporation is still working on Dreamchaser, but it's only under a cargo contract with NASA, so it will lack the ability to carry people. Also, SNC isn't exactly a "big player" in aerospace. You're playing (quite) long odds if you think they'll eventually dominate manned space travel. The USAF is funding Experimental Spaceplane program (XS-1), which sounds really cool, but it's nothing more than a (smallish) winged reusable first stage. It's very hard for me to see this thing being cheaper than a reusable Falcon 9 first stage. There are several reasons for this. First the contractor is Boeing. Second, the thing will use what's left of the parts of old SSMEs assembled into working engines (i.e. the bits NASA isn't planning on using for SLS) and the SSME is not known for being a "cheap" engine by any stretch of the imagination. Third, LH2 is not a very dense fuel so this will result in a quite large "space plane" when compared to say a LOX/kerosene stage. Fourth, winged landing vehicles are more complex than a VTVL in aerodynamics, structures, dynamics and control, and etc. Costs scale more closely with complexity than size, but in the case of the XS-1, it's got complexity and size as its drawbacks. So, any way you run the accounting, I have a feeling XS-1 is going to be a dismal (economic) failure. Despite the prejudices of the USAF, there is nothing magic about wheels on a runway that will make "spaceplanes" inexpensive to operate. So, from my point of view, we're not sitting on the cusp of a resurgence in "space planes". They're just too expensive to develop and too expensive to fly compared to their simpler, cheaper, VTVL counterparts. I'd also note that in the consumer world, the market of small flying machines is dominated by quad copters, not fixed wing aircraft. VTVL tech has literally matured to the point where it's cheap enough and easy enough to fly that you can buy one in the children's toy aisle for less than $100. Jeff -- All opinions posted by me on Usenet News are mine, and mine alone. These posts do not reflect the opinions of my family, friends, employer, or any organization that I am a member of. |
#7
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U.S. astronauts are climbing back into space capsules. Here's how they've improved over the past 50 years
"Greg \(Strider\) Moore" wrote:
"Fred J. McCall" wrote in message .. . wrote: "In 1961, an American astronaut reached space for the first time and soared through the heavens in a gumdrop-shaped capsule. Since then, people have flown to the moon, created space planes and designed rockets that return to Earth for precision landings. But when astronauts lift off next year from U.S. soil for the first time in six years, their vehicle of choice will be another capsule." See: http://www.latimes.com/business/la-f...htmlstory.html How do the benefits of capsules and spaceplanes compare? Capsules have lower dry mass for the cargo they carry, since you're not carrying along all that lifting structure. I was rather disappointed to see SpaceX back away from a powered landing on land for the Dragon V2, since that would have addressed one of the advantages of spaceplanes in that they don't require 'recovery forces' to fish them out of the water. Small spaceplanes tend to be more 'reusable' than capsules. However, the fiasco that was the Space Shuttle backed everyone away from the idea of spaceplanes. My understanding is that NASA is the one insisting on a water landing for Dragon V2, but SpaceX for its own missions still plans to ultimately do land landings. They changed that plan in the last few months. It's apparently too hard to get it certified as safe so that they're allowed to launch with that intent, so it's all water landings for everyone now and they're not working on powered landings anymore. I expect we'll eventually see us move back towards small spaceplans/lifting body designs in a few decades, but it'll take some time. I think the best approach is small spaceplanes for people and small cargos and big dumb expendables for big cargo. But I think the Shuttle soured the spaceplane punch for a long while to come. -- "We come into the world and take our chances. Fate is just the weight of circumstances. That's the way that Lady Luck dances. Roll the bones...." -- "Roll The Bones", Rush |
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U.S. astronauts are climbing back into space capsules. Here's how they've improved over the past 50 years
JF Mezei wrote:
On 2017-09-20 07:13, Jeff Findley wrote: The USAF is funding Experimental Spaceplane program (XS-1), which sounds really cool, but it's nothing more than a (smallish) winged reusable first stage. Would a winged 1st stage have far greater landing range after it released it load? (SpaceX has to have a barge out in ocean for certain launches because stage1 doesn't have fuel to return to land). Unlikely. What it would do is decrease the amount of fuel you'd have to reserve for recovery, since it could use aerodynamic forces instead. snip It's very hard for me to see this thing being cheaper than a reusable Falcon 9 first stage. From a software point of view, would designing landing system for winged vehicle be simpler than a pure rocket? It took SpaceX a while to develop and a number of failures to fine tune the system. It's probably somewhat easier, but remember that SpaceX issues were largely related to how throttleable their engines were. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw |
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U.S. astronauts are climbing back into space capsules. Here's how they've improved over the past 50 years
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U.S. astronauts are climbing back into space capsules. Here's how they've improved over the past 50 years
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